System for identifying and duplicating master keys

ABSTRACT

A system for duplicating a master key includes a mechanism for receiving and positioning a master key. The master key defines a major key axis and an intermediate key axis along which a key blade variably extends, and a minor key axis along a key thickness. Optical path components direct a light beam along the minor key axis. The light beam impinges upon the key blade. A portion of the light beam traverses the key blade. A detector receives the portion of the light beam that traverses the key blade. An apparatus imparts relative motion along the major key axis between the light beam and the master key. The light beam scans along the major key axis of the master key. A processor receives a signal from the detector as the beam scans along the major key axis and generates information usable for defining the machining of a duplicate key.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a continuation of U.S. patent application Ser. No. 15/728,074,filed on Oct. 9, 2017, which is a continuation of U.S. patentapplication Ser. No. 15/191,071 (now U.S. Pat. No. 9,808,900), filed onJun. 23, 2016, which claims the benefit of U.S. Provisional ApplicationNo. 62/185,078, filed Jun. 26, 2015, hereby incorporated herein byreference.

TECHNICAL FIELD

This is directed to the field of key duplication and, more specifically,to the field of apparatuses and methods of automatically analyzingmaster keys in an automated and very accurate manner.

BACKGROUND

Various key duplication systems exist for receiving and duplicating amaster key. More recent key duplication systems can be automated. Suchsystems have to perform certain functions.

First, a proper key blank needs to be selected. A typical key blank ischaracterized factors such as a keyway which is defined by a geometry ofa cross-section of a key. An improperly selected key blank will resultin an attempted duplicate that cannot be inserted into a lock. Somesystems rely on a user to select a proper key blank. This may lead tohuman error. There is a desire to provide highly reliable automated keyblank selection.

Second, the master key needs to be analyzed to obtain the correct“bitting pattern” which defines the shape of a master key blade. Animproper determination of the bitting pattern will result in the key notopening a particular lock.

There is an ongoing need to improve the reliability and accuracy ofsystems that select key blanks and determine bitting patterns for thepurpose of key duplication.

SUMMARY

A system and method of the present disclosure concerns an accurate andreliable system and method for analyzing and machining a duplicate for amaster key. The master key geometrically defines three mutuallyorthogonal axes including a major key axis which is the longest axis ofthe master key, an intermediate key axis along which a key bladevariably extends, and a minor key axis along a key thickness. Thevariable extent of the key blade defines a bitting of the master key.

In one aspect of the disclosure a key duplication system includesvarious major components including the following: (1) a clampingmechanism for receiving and positioning the master key; (2) optical pathcomponents that direct a light beam along the minor key axis whereby thelight beam impinges upon the key blade such that a portion of the lightbeam traverses the key blade; (3) a detector that receives the portionof the light beam that traverses the key blade; (4) an apparatus thatimparts relative motion along the major key axis between the light beamand the master key whereby the light beam scans along the major key axisof the master key; (5) a processor that receives a signal from thedetector as the beam scans along the major key axis and generatesinformation useable for defining the machining of a duplicate key.

In one implementation the clamping mechanism holds the master key in afixed stationary location. Thus the relative motion between the lightbeam and the master key along the major key axis is a result of motionof the light beam.

In another implementation the key duplication system includes a moveablestage configured to move along the major key axis. The optical pathcomponents are affixed to the moveable stage whereby the moveable stageis the apparatus that imparts the relative motion along the major keyaxis between the light beam and the master key. In one embodiment theoptical path components include beam directing components that redirectthe light beam between a laser and the key blade and/or between the keyblade and a detector. In a more particular embodiment the optics includefirst and second beam directing components. The first beam directingcomponent redirects the light beam between the laser and the key blade.The second beam directing component redirects the light beam between thekey blade and the detector. In yet a more particular embodiment thefirst beam directing component is a first mirror that receives the lightbeam directed along a −Y direction along the major key axis and thenredirects the light to a +X direction along the minor key axis. Thesecond beam directing component is a second mirror that receives thelight beam from the first mirror after having traversed the key bladeand then redirects the light to a +Y direction along the major key axis.

In a further implementation the key duplication system includes amoveable stage configured to move along the major key axis. The opticalpath components that direct the light beam are affixed to the moveablestage whereby movement of the optical stage along the major key axisimparts the relative motion between the light beam and the master key.The optical path components include a light source and a detector. Inone embodiment the light source is a laser. In another embodiment thedetector is a position sensitive detector (PSD).

In yet another implementation the optical path components include (1) alaser for generating a light beam, (2) a slit for forming the beamwhereby the beam exiting the slit is narrowed along a first axis andwide along the intermediate key axis to allow the beam to partiallytraverse the master key blade. The light beam impinging upon andtraversing the blade is narrow along the major key axis (Y). Thisprovides a higher resolution in analyzing the bitting pattern. The lightbeam impinging upon and traversing the blade is wide along theintermediate key axis (Z). This enables the measurement of a wide rangeof bitting patterns. The detector is a one dimensional positionsensitive detector (PSD) with the long axis of the PSD aligned with theintermediate key axis Z. In one embodiment the location of the centroidof the light beam along the intermediate key axis Z is detected as ameasure of the height of the key blade.

In another aspect of the disclosure, a method for duplicating a masterkey includes: (1) receiving and clamping the master key; (2) generatinga light beam extending along the minor key axis and partially traversingthe key blade before reaching a detector; (3) imparting relative motionalong the major key axis between the light beam and the master keywhereby the light beam scans along the major key axis; (4) the detectorgenerating a signal versus time that corresponds to the height orprofile of the key blade along the intermediate axis.

In one implementation, receiving and clamping the master key includesaffixing the master key in a stationary configuration. The relativemotion is due to motion of the light beam.

In another implementation, optical path components directing the lightbeam are affixed to a movable stage. Motion of the moveable stagethereby imparts the relative motion between the light beam and themaster key. In one embodiment generating the light beam includesactivating a laser. In a further embodiment the optical path componentsinclude first and second beam directing components and the methodfurther includes receiving the light beam from the laser, the first beamdirecting component redirecting the light beam from the laser toward thekey blade, the second beam directing component redirecting the lightbeam from the key blade to the detector. In yet a more specificembodiment the first beam directing component is a first mirror and thesecond beam directing component is a second mirror, the first mirrorredirecting the light beam from along the major key axis to the minorkey axis, the second mirror redirecting the light beam from along theminor key axis to the major key axis.

In a further implementation a camera is mounted on a moveable stage andthe method further comprising the camera capturing an image of the endof the key. In one embodiment the detector is used to detect anddetermine a location of a distal end of the master key. The determinedlocation is used by the system to properly position the camera.

In a further aspect of the disclosure a key duplication system includes:a mechanism for receiving and clamping a master key in a fixed position,the master key defining a major key axis, an intermediate key axis alongwhich a key blade variably extends, and a minor key axis along a keythickness; a light source that generates a light beam; a detector; amoveable stage configured to move along the major key axis; optical pathcomponents affixed to the movable stage that receive the light beam fromthe light source and direct the light beam to partially traverse the keyblade and then to pass the light beam from the key blade to the detectorwhereby motion of the moveable stage causes the light beam to scan alongthe major key axis; a processor that receives a signal from the detectorand provides information used to machine a duplicate key.

In one implementation the light source and/or the detector are affixedto the moveable stage. In one embodiment the light source is a laser. Ina further embodiment the detector is a position sensitive detector(PSD). The PSD detects a light level and/or the position of a light spotreceived via the light beam. In a particular embodiment the PSD is aone-dimensional PSD that is particularly sensitive to a spot of lightthat is elongate along the intermediate key axis Z. The PSD has an axisof elongation that is aligned with the intermediate key axis Z.

In another implementation the optical path components include a firstbeam directing component and a second beam directing component. Thefirst beam directing component receives the light beam along the majorkey axis and redirects the light beam along the minor key axis beforethe light beam reaches the key blade. The second beam directingcomponent receives the light beam along the minor key axis from the keyblade and redirects the light beam along the major key axis before thelight beam reaches the detector.

In a further implementation the optical path components include a firstmirror and a second mirror. The first mirror receives the light beamfrom the light source travelling in a −Y direction along the major keyaxis and redirects the light beam to a +X direction along the minor keyaxis before the light beam reaches the key blade. The second mirrorreceives the light beam travelling in a +X direction from the key bladeand redirects the light beam to a +Y direction before the light beamreaches the detector.

In yet another implementation a camera is mounted to the moveable stage.The camera is for capturing an end image of the key for identifying aproper key blank.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1A is an isometric view of an exemplary master key.

FIG. 1B is a side view of an exemplary master key.

FIG. 1C is a cross sectional view of an exemplary master keyillustrating the keyway.

FIG. 2 is a schematic plan view of an exemplary system 20 utilized foranalyzing and duplicating a master key.

FIG. 3 is a side view depicting a light beam partially traversing theblade of a master key.

FIG. 4 is a schematic plan view of an exemplary system 20 utilized foranalyzing and duplicating a master key.

FIG. 5 is an electrical block diagram of certain components of a system20 utilized for analyzing and duplicating a master key.

FIG. 6 is a flowchart representation of an exemplary embodiment of amethod of duplicating a master key using the system depicted in FIGS. 2,3, 4, and 5.

FIG. 7 is a flowchart representation of an alternative embodiment of amethod of duplicating a master key using the system depicted in FIGS. 2,3, 4, and 5.

FIG. 8 is a schematic plan or top view of a certain components of analternative system 20′ utilized for analyzing and duplicating a masterkey.

DETAILED DESCRIPTION

FIGS. 1A, 1B, and 1C are isometric, side, and cross sectional views ofan exemplary master key 2 to be analyzed for purposes of duplication.According to this description, a master key 2 is any key that a user orcustomer desires to duplicate such as a house key, a key to a storageunit, a key to automobile, or any other key that mechanically opens orcloses a lock.

To illustrate master key 2, three mutually orthogonal axes X, Y, and Zare defined. Minor key axis X is defined along the thickness of masterkey 2. Major key axis Y is defined along the longest axis of master key2. Head 4 and distal end 6 of master key 2 are disposed along major keyaxis Y. Intermediate key axis Z is the defined as the direction alongwhich key blade 8 variably extends.

Master key 2 is uniquely defined by various factors including a (1)keyway 10, and (2) bittings or teeth formed into key blade 8. Keyway 10is defined by a cross section 10 of master key 2. The keyway 10 hasfeatures such as channels 12 and ridges 14 that allow the master key 2to slide into a particular lock. The channels 12 and ridges 14 define avariable extent of a portion of key blade 8 along minor key axis X.

Key blade 8 extends variably along intermediate axis Z. The variableextent of key blade 8 defines features such as key teeth 16. Thevariable extent of key blade 8 defines the bitting of master key 2. Thebitting of master key 2 determines which specific lock master key 2 canunlock and lock.

FIG. 2 is a schematic representation of an exemplary system 20 foranalyzing a master key 2 to be duplicated. System 20 defines an opticalpath 22 along which a light beam 24 travels between a light source 26and a detector 28. The light beam 24 traverses and overlaps a portion ofkey blade 8. An amount of light that reaches detector 28 is a functionof the height of key blade 8 along the intermediate key axis Z. System20 imparts a relative motion along major key axis Y between light beam24 and master key 2. In doing so the detector 28 receives a variableamount of light versus time that corresponds to the extent of key blade8 along intermediate key axis Z.

The optical path 22 is defined or formed by a number of optical pathcomponents 23. The optical path components 23 can include one or more ofa light source 26, a detector 28, a beam shaping component 30, and beamdirecting components 32 and 34. In an exemplary embodiment the lightsource 26 is a laser. Detector 28 is a position sensitive detector (PSD)28. Beam shaping component 30 is a slit 30. Optical path components 23can also include a cylindrical lens 31 for collimating the light beam24. Beam directing components 32 and 34 include a first beam directingcomponent 32 and a second beam directing component 34. The first beamdirecting component 32 receives the light beam 24 from light source 26and redirects the light beam 24 toward the key blade 8. The second beamdirecting component 34 receives the light beam 24 from the key blade 8and redirects the light beam 24 toward the detector 28. Beam directingcomponents 32 and 34 can be mirrors 32 and 34 respectively. In analternative embodiment beam directing components 32 and 34 can be prisms32 and 34 respectively.

According to a particular embodiment light source 26 is a laser thatgenerates beam 24 that travels in a −Y direction along the major keyaxis Y. Light beam 24 first encounters slit 30 that reduces thecross-sectional area of light beam 24 and forms a beam having a crosssection that is elongate along intermediate key axis Z and otherwisenarrowed orthogonally to the direction of travel. Next, the light beam24 encounters first mirror 32 that deflects light beam 24 from the −Ydirection to the +X direction along the minor key axis X. Light beam 24then impinges upon key blade 8 which over which a portion of the lightbeam 24 is able to traverse and to continue along in the +X direction.Next, light beam 24 encounters second mirror 34 which deflects lightbeam 24 from the +X direction to the +Y direction. Light beam thentravels to detector 28.

Detector 28 is a position sensitive detector (PSD) 28. PSD 28 receiveslight beam 24 and generates a signal that is related to a location ZC ofa centroid along intermediate axis Z of the light beam 24 that hastraversed key blade 8. In one embodiment the PSD 28 outputs two signalsthat are processed in order to determine the centroid Z-axis coordinateZC. The centroid Z-axis coordinate ZC will tend to linearly increasewith the height of key blade 8 over which light beam traverses. Thus thevalue of ZC over time can be used to compute the profile or bitting ofmaster key 2.

A side view of a portion of system 20 is illustrated in FIG. 3 withemphasis on the effect of key blade 8 upon light beam 24. Mirror 34 iseliminated from FIG. 3 for illustrative simplicity. Light beam 24travels along direction 36 and partially impinges upon key blade 8. Onlyan upper portion of light beam 24 traverses key blade 8 because keyblade 8 blocks a portion of light beam 24. The amount of light beam 24that traverses key blade 8 is a function of the extent of key blade 8along intermediate key axis Z. PSD 28 generates an output signal that isa function of the amount of light received past key blade 8. Thus theoutput signal of PSD 28 varies with the vertical extent of key blade 8along intermediate axis Z. The output signal of PSD 28 is processed todetermine the centroid coordinate ZC of the light beam 24 that traversesthe key blade 8. As the key blade extends farther in the +Z directionthe centroid coordinate ZC of the light beam 24 that traverses key blade8 has a correspondingly increased Z-value.

Referring to FIGS. 2 and 3, the function and advantage of slit 30 isapparent. Slit 30 reduces the width of light beam 24 along the Z and Yaxes just before the light beam reaches key blade 8 (after first mirror32). After the light beam 24 has reflected from mirror 32 the width ofthe light beam 24 is reduced along the major key axis Y while stillrelatively wide along the intermediate key axis Z as the light beam 24partially traverse the key blade 8. The reduction of light beam 24 widthalong the major key axis Y has the effect of increasing the resolutionof system 20 which enables a more accurate measurement of key bitting.At the same time, the wider light beam 24 along the intermediate keyaxis Z increases the range of extent of key blade 8 along theintermediate key axis Z that can be measured.

In one embodiment the light beam 24 has a width along the intermediatekey axis Z that is in a range of 5 millimeters to 10 millimeters. In amore particular embodiment the width of light beam 24 along theintermediate key axis Z is in a range of 5 millimeters to 7 millimeters.In one particular embodiment the width of light beam 24 along theintermediate key axis Z is 6 about millimeters. This will generallyaccommodate keys having a blade width measured along intermediate keyaxis Z of up to 5 millimeters. Minimizing the width of the light beam 24along the intermediate key axis 8 helps to maximize a sensitivity to theheight of blade 8 along intermediate key axis 8. Other light beam widthsalong intermediate key axis Z may be utilized depending on the expectedwidths of key blade 8 along intermediate axis Z. In an exemplaryembodiment the with of the beam along intermediate key axis Z justexceeds the maximum expected key blade width.

In one embodiment the light beam 24 has a width along the major key axisY that is less than 1 millimeter. In another embodiment the light beam24 has a width along the major key axis Y that is less than 0.5millimeter. In a further embodiment the light beam 24 has a width alongthe major key axis Y that is about 0.25 millimeter.

Referring back to FIG. 2 the master key 2 is held in a stationaryposition by a clamping mechanism 38. System 20 also includes moveablestage 40 that is configured to linearly translate along key major axisY. Affixed or mounted to moveable stage 40 are optical path componentsincluding laser 26, mirrors 32 and 34, and PSD 28. Thus, the motion ofmoveable stage 40 defines and imparts the motion of optical path 22. Themotion of stage 40 along major key axis Y determines the relative motionbetween light beam 24 and key blade 8 whereby the light beam 24 scansalong key blade 8. The scanning of light beam 24 along key blade 8results in a light beam 24 whose cross sectional area varies with timereaching PSD 28. The scanning of light beam 24 along key blade 8 alsoresults in a light beam 24 that traverses key blade 8 and reaches PSD 28whose centroid coordinate ZC varies with time. The time variation is afunction of height of key blade 8 along intermediate key axis Z. PSDthen outputs a time varying signal that is indicative of or correlateswith the profile of key blade 8 along intermediate axis Z.

FIG. 4 is a schematic representation of system 20 to illustrate asubsystem including light sources 42 and camera 44. Light sources 44 canbe light emitting diodes (LEDs) 42 that are positioned to illuminate asurface of distal end 6 of master key 2. Camera 44 receives lightgenerally reflected in the +Y direction from distal end 6 to provide animage that represents the keyway 10 (see FIG. 1C). The resultant imagemay then be used to determine a key blank having the proper keyway forduplication of master key 2. In one embodiment light sources 42 andcamera 44 are mounted to moveable stage 40. In another embodiment lightsources 42 are fixed and camera 44 is mounted to moveable stage 40. Inyet another embodiment light sources 42 are fixed and camera 44 isconfigured to translate independently of moveable stage 40.

FIG. 5 depicts an exemplary electrical block diagram of circuitry andvarious components of the system 20 previously described with respect toFIGS. 2, 3, and 4. System 20 includes a main controller board (PCBA) 50that is coupled to various system components and to a computer 52. It isto be understood that certain components of FIG. 5 have interconnectionsthat for purposes of simplicity are not illustrated. Communicationbetween PCBA 50 and computer 52 can be accomplished via a universalserial bus (USB) port 54. Computer 52 sends control commands to PCBA 50and receives data from PCBA 50 that is usable to determine a proper keyblank and for machining key blade 8 to provide a duplicate of master key2. In one embodiment PCBA 50 is mounted to stage 40 and is mechanicallycoupled to PSD 28 as is depicted in FIG. 3.

PCBA 50 includes a laser driver 56 for providing power to laser 26. PCBAalso includes a microcontroller 58 that receives a signal originatingfrom PSD 28 that is indicative of an amount of light traversing keyblade 8. An analog signal from PSD 28 is amplified by amplifier 57 andthen digitized by analog to digital converter 59 before reachingmicrocontroller 58. Microcontroller 58 processes the digital signal fromanalog to digital converter 59 and sends information to computer 52 thatis indicative of the height of key blade 8 along intermediate key bladeaxis Z via the USB port 54.

In the illustrative embodiment sensor 28 outputs two analog signals. Theamplified and digitized versions of the two signals are received bymicrocontroller 58. The two signals are processed by microcontroller 58to determine a position coordinate ZC of a centroid of light beam 24that has traversed key blade 8.

PCBA 50 includes a clamp driver 60 for operating clamping mechanism 38.In the illustrative embodiment clamping mechanism 38 includes verticalclamp 38V and horizontal clamp 38H for clamping master key 2.

PCBA 50 includes a motor driver 62 for controlling a stepper motor 64for translating moveable stage 40 along major key axis Y. Motor driverreceives positional feedback from encoder 66.

PCBA 50 includes an LED driver 68 for driving LEDs 42 for illuminatingthe distal end 6 of master key 2. Camera 44 provides information tocomputer 52 that is indicative of an end image received from distal end6 of master key 2.

FIG. 6 is a flowchart depicting an exemplary process 100 for machining aduplicate of master key 2. For this exemplary embodiment the system 20described with respect to FIGS. 2, 3, 4, and 5 is utilized. For thisembodiment various optical path components 23 including laser 26, PSD28, first mirror 32, and second mirror 34 are affixed to moveable stage40 which moves linearly along the major key axis Y.

According to initial condition 102, the moveable stage is at a homeposition which is as far to the −Y position as possible. According tostep 104, a master key 2 is received in clamping mechanism 38 and theprocess 100 is started. Also according to step 104 the master key 2 isclamped by clamping mechanism 38.

According to step 106 the stepper motor 64 is activated to scan moveablestage 40 in the +Y direction along the major key axis Y whereby thelight beam 24 is moved or scanned toward the distal end 6 of master key2. As the light beam 24 is scanned the bitting information is capturedaccording to step 108. As part of step 108 the vertical extent of lightbeam 24 along intermediate key axis Y reaching PSD 28 is variedaccording to the extent of key blade 8 along intermediate axis Y. Thisvariation results in a varying output signal from PSD 28 that isreceived and processed by microcontroller 58. Microcontroller 58 thengenerates and transmits information indicative of the bitting of masterkey 2 to computer 52.

According to step 110 a Y coordinate of the distal end 6 of master key 2is determined according to the signal generated by PSD 28. When thelight beam 24 passes the distal end 6 the computed centroid of lightbeam 24 along Z will be a minimum and a constant. The Y-positionreceived from encoder 66 when the signal is first maximized will then bethat of the distal end 6 of the key.

According to step 112 the system 20 uses the Y-position of distal end 6to determine the proper positioning of camera 44 to focus on the distalend 6 of master key 2. Also according to step 112 the camera 44 is movedinto the position for focusing on distal end 6.

According to step 114 camera 44 captures an image of the distal end 6 ofmaster key 2. According to step 116 the image of distal end 6 and thebitting information (captured in step 108) are used to determine andenable a selection of a proper key blank. According to step 118 theselected key blank is machined using the bitting determined from step108.

According to step 120 the master key 2 is released and removed fromclamping mechanism 38. Also as part of step 120 the movable stage 40moves in the −Y direction and back to the home position described withrespect to step 102.

FIG. 7 is a flowchart depicting an alternative exemplary process 150 formachining a duplicate of master key 2. For process 150 the system 20described with respect to FIGS. 2, 3, 4, and 5 is utilized. For thisembodiment various optical path components 23 including laser 26, PSD28, first mirror 32, and second mirror 34 are affixed to moveable stage40 which moves linearly along the major key axis Y.

According to initial condition 152 moveable carriage starts at a homeposition that is as far in the +Y direction along the major key axis Yas possible. In this position the light beam 24 will not intersect amaster key 2 having the largest distal dimension Y(distal end 6) alongmajor key axis Y.

According to step 154, a master key 2 is received in clamping mechanism38 and the process 150 is started. Also according to step 154 the masterkey 2 is clamped by clamping mechanism 38.

According to step 156 the stage begins to move in the −Y direction whilecamera 44 attempts to focus on the distal end 6 of master key 2.According to step 158 camera 44 detects the end of master key 2 anddetermines a proper position of movable carriage 40 for proper focusingof camera 44 upon the distal end 6. According to step 160 the camera 44captures an image of distal end 6 of master key 2. According to step 162the computer 52 utilizes the image from step 160 to identify and enableselection of a proper key blank for duplication of master key 2.

Also according to step 158 system 20 (computer 52 included) determines aY-location of distal end 6 of master key 2. Thus the system can movequickly to an optimal position according to step 164. According to step166 light beam 24 is scanned along key blade 8. Also according to step166 PSD 28 receives the variable light beam 24 versus time and outputs asignal to microcontroller 58. Microcontroller 58 provides information tocomputer 52 indicative of the bitting of master key 2. Thus the bittinginformation of master key 2 is captured according to step 168.

According to step 170 a new key is machined from the selected key blank.According to step 172 the master key 2 is unclamped and the carriage isreturned to a retraced (+Y) home position as it started according to152.

Other variations are possible. For example, the image obtained from step160 and the bitting information from step 168 may be utilized to selectthe proper key blank.

An exemplary embodiment of system 20 has been described in which amotion of light beam 24 along major key axis Y is imparted by the motionof optical path components 23 mounted or affixed to moveable stage 40.An alternative embodiment of system 20 is depicted as system 20′ in FIG.8 in which optical path components 23′ are stationary during an opticalscan of master key 2. Stationary optical path components 23′ cause lightbeam 24 to scan along major key axis Y of master key 2 without motion ofthe stationary optical path components 23′.

System 20′ includes master key 2, clamping mechanism 38, laser 26, slit30, lens 31 (not shown in FIG. 8), detector 28, and camera 44 that areall similar to like-numbered elements described with respect to FIG. 2.System 20′ also includes scan module 200, first curved mirror 202, andsecond curved mirror 204. Scan module 200 can take on a number of forms.One example is a rotating galvanometer mirror. Another example is arotating polygon mirror.

In the exemplary embodiment of FIG. 8, scan module 200 causes light beam24 to rotate back and forth as indicate by the dashed lines. Curvedmirror 202 serves to change the path of light beam 24 such that itlinearly scans across blade 8 of master key 2. Curved mirror 204 thencauses light beam 24 to converge upon detector 28. The output fromdetector 28 in FIG. 8 is similar to that described with respect to FIG.2.

Other variations of stationary optical components 23′ are possible toeliminate a need for mechanical motion during scanning. For example, thescan module 200 can be designed to impart linear motion of light beam24. Reflective optics for conveying the scanning beam to the key blade 8and the detector 28 would then be selected to accommodate the linearscanning motion of light beam 24 for such an embodiment.

Referring back to FIG. 2, an exemplary embodiment has been described inwhich clamping mechanism 38 is fixed while light beam 24 moves acrosskey blade 8. Alternatively, system 20 may be designed in which clampingmechanism 38 translates along major key axis Y while light beam 24 isstationary. This will result in essentially the same output fromdetector 28.

Thus, the specific embodiments and applications thereof described aboveare for illustrative purposes only and do not preclude modifications andvariations encompassed by the scope of the following claims.

The invention claimed is:
 1. A system for duplicating a master key comprising: a mechanism for receiving and positioning a master key, wherein the master key defines a major key axis, an intermediate key axis along which a key blade variably extends, and a minor key axis along a key thickness; one or more optical path components that direct a light beam along the minor key axis; one or more apparatus that imparts relative motion along the major key axis between the light beam and the master key such that the light beam scans along the major key axis; a detector that receives at least a portion of the light beam; a processor that receives a signal from the detector as the light beam scans along the major key axis and generates bitting information usable for duplicating the master key; and a camera configured to capture an image of the distal end of the master key, wherein the image is usable for identifying a proper key blank for duplicating the master key.
 2. The system of claim 1, wherein the light beam impinges upon the key blade such that a portion of the light beam is blocked by the key blade and another portion of the light beam traverses across the major, axis of the key blade, and wherein the detector receives the portion of the light beam that traverses the key blade.
 3. The system of claim 1, wherein the mechanism holds the master key in a fixed location and the relative motion is a result of motion of the light beam.
 4. The system of claim 1, further comprising a laser for generating the light beam.
 5. A method for duplicating a master key comprising: receiving and positioning a master key, wherein the master key defines a major key axis, an intermediate axis along which a key blade variably extends, and a minor key axis along a key thickness; generating a light beam and directing the light beam along the minor key axis; imparting relative motion along the major key axis between the light beam and the master key such that the light beam scans along the major key axis; determining bitting information for the master key based on a detection of at least a portion of the light beam; and capturing an image of the distal end of the master key, wherein the image is usable for identifying a proper key blank for duplicating the master key.
 6. The method of claim 5, further comprising: generating a detection signal versus time based on the detection of at least a portion of the light beam, the detection signal verses time corresponding to a height of the key blade along the intermediate axis; and using the detection signal versus time to determining the bitting information.
 7. The method of claim 5 wherein receiving and positioning the master key includes affixing the master key in a stationary configuration.
 8. The method of claim 5 wherein generating the light beam includes activating a laser. 